/*
 * file:		include/lib/float.h
 * auther:		Jason Hu
 * time:		2020/2/14
 * copyright:	(C) 2018-2020 by Book OS developers. All rights reserved.
 */

#ifndef _LIB_FLOAT_H
#define _LIB_FLOAT_H

/* Copyright (C) 2002, 2007, 2008, 2009 Free Software Foundation, Inc.

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.

GCC is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.

You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
<http://www.gnu.org/licenses/>.  */

/*
 * ISO C Standard:  5.2.4.2.2  Characteristics of floating types <float.h>
 */

#ifndef _FLOAT_H___
#define _FLOAT_H___

/* Radix of exponent representation, b. */
#undef FLT_RADIX
#define FLT_RADIX        __FLT_RADIX__

/* Number of base-FLT_RADIX digits in the significand, p.  */
#undef FLT_MANT_DIG
#undef DBL_MANT_DIG
#undef LDBL_MANT_DIG
#define FLT_MANT_DIG        __FLT_MANT_DIG__
#define DBL_MANT_DIG        __DBL_MANT_DIG__
#define LDBL_MANT_DIG        __LDBL_MANT_DIG__

/* Number of decimal digits, q, such that any floating-point number with q
   decimal digits can be rounded into a floating-point number with p radix b
   digits and back again without change to the q decimal digits,

        p * log10(b)                        if b is a power of 10
        floor((p - 1) * log10(b))        otherwise
*/
#undef FLT_DIG
#undef DBL_DIG
#undef LDBL_DIG
#define FLT_DIG                __FLT_DIG__
#define DBL_DIG                __DBL_DIG__
#define LDBL_DIG        __LDBL_DIG__

/* Minimum int x such that FLT_RADIX**(x-1) is a normalized float, emin */
#undef FLT_MIN_EXP
#undef DBL_MIN_EXP
#undef LDBL_MIN_EXP
#define FLT_MIN_EXP        __FLT_MIN_EXP__
#define DBL_MIN_EXP        __DBL_MIN_EXP__
#define LDBL_MIN_EXP        __LDBL_MIN_EXP__

/* Minimum negative integer such that 10 raised to that power is in the
   range of normalized floating-point numbers,

        ceil(log10(b) * (emin - 1))
*/
#undef FLT_MIN_10_EXP
#undef DBL_MIN_10_EXP
#undef LDBL_MIN_10_EXP
#define FLT_MIN_10_EXP        __FLT_MIN_10_EXP__
#define DBL_MIN_10_EXP        __DBL_MIN_10_EXP__
#define LDBL_MIN_10_EXP        __LDBL_MIN_10_EXP__

/* Maximum int x such that FLT_RADIX**(x-1) is a representable float, emax.  */
#undef FLT_MAX_EXP
#undef DBL_MAX_EXP
#undef LDBL_MAX_EXP
#define FLT_MAX_EXP        __FLT_MAX_EXP__
#define DBL_MAX_EXP        __DBL_MAX_EXP__
#define LDBL_MAX_EXP        __LDBL_MAX_EXP__

/* Maximum integer such that 10 raised to that power is in the range of
   representable finite floating-point numbers,

        floor(log10((1 - b**-p) * b**emax))
*/
#undef FLT_MAX_10_EXP
#undef DBL_MAX_10_EXP
#undef LDBL_MAX_10_EXP
#define FLT_MAX_10_EXP        __FLT_MAX_10_EXP__
#define DBL_MAX_10_EXP        __DBL_MAX_10_EXP__
#define LDBL_MAX_10_EXP        __LDBL_MAX_10_EXP__

/* Maximum representable finite floating-point number,

        (1 - b**-p) * b**emax
*/
#undef FLT_MAX
#undef DBL_MAX
#undef LDBL_MAX
#define FLT_MAX                __FLT_MAX__
#define DBL_MAX                __DBL_MAX__
#define LDBL_MAX        __LDBL_MAX__

/* The difference between 1 and the least value greater than 1 that is
   representable in the given floating point type, b**1-p.  */
#undef FLT_EPSILON
#undef DBL_EPSILON
#undef LDBL_EPSILON
#define FLT_EPSILON        __FLT_EPSILON__
#define DBL_EPSILON        __DBL_EPSILON__
#define LDBL_EPSILON        __LDBL_EPSILON__

/* Minimum normalized positive floating-point number, b**(emin - 1).  */
#undef FLT_MIN
#undef DBL_MIN
#undef LDBL_MIN
#define FLT_MIN                __FLT_MIN__
#define DBL_MIN                __DBL_MIN__
#define LDBL_MIN        __LDBL_MIN__

/* Addition rounds to 0: zero, 1: nearest, 2: +inf, 3: -inf, -1: unknown.  */
/* ??? This is supposed to change with calls to fesetround in <fenv.h>.  */
#undef FLT_ROUNDS
#define FLT_ROUNDS 1

#if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
/* The floating-point expression evaluation method.
        -1  indeterminate
         0  evaluate all operations and constants just to the range and
            precision of the type
         1  evaluate operations and constants of type float and double
            to the range and precision of the double type, evaluate
            long double operations and constants to the range and
            precision of the long double type
         2  evaluate all operations and constants to the range and
            precision of the long double type

   ??? This ought to change with the setting of the fp control word;
   the value provided by the compiler assumes the widest setting.  */
#undef FLT_EVAL_METHOD
#define FLT_EVAL_METHOD        __FLT_EVAL_METHOD__

/* Number of decimal digits, n, such that any floating-point number in the
   widest supported floating type with pmax radix b digits can be rounded
   to a floating-point number with n decimal digits and back again without
   change to the value,

        pmax * log10(b)                        if b is a power of 10
        ceil(1 + pmax * log10(b))        otherwise
*/
#undef DECIMAL_DIG
#define DECIMAL_DIG        __DECIMAL_DIG__

#endif /* C99 */

#ifdef __STDC_WANT_DEC_FP__
/* Draft Technical Report 24732, extension for decimal floating-point
   arithmetic: Characteristic of decimal floating types <float.h>.  */

/* Number of base-FLT_RADIX digits in the significand, p.  */
#undef DEC32_MANT_DIG
#undef DEC64_MANT_DIG
#undef DEC128_MANT_DIG
#define DEC32_MANT_DIG        __DEC32_MANT_DIG__
#define DEC64_MANT_DIG        __DEC64_MANT_DIG__
#define DEC128_MANT_DIG        __DEC128_MANT_DIG__

/* Minimum exponent. */
#undef DEC32_MIN_EXP
#undef DEC64_MIN_EXP
#undef DEC128_MIN_EXP
#define DEC32_MIN_EXP        __DEC32_MIN_EXP__
#define DEC64_MIN_EXP        __DEC64_MIN_EXP__
#define DEC128_MIN_EXP        __DEC128_MIN_EXP__

/* Maximum exponent. */
#undef DEC32_MAX_EXP
#undef DEC64_MAX_EXP
#undef DEC128_MAX_EXP
#define DEC32_MAX_EXP        __DEC32_MAX_EXP__
#define DEC64_MAX_EXP        __DEC64_MAX_EXP__
#define DEC128_MAX_EXP        __DEC128_MAX_EXP__

/* Maximum representable finite decimal floating-point number
   (there are 6, 15, and 33 9s after the decimal points respectively). */
#undef DEC32_MAX
#undef DEC64_MAX
#undef DEC128_MAX
#define DEC32_MAX   __DEC32_MAX__
#define DEC64_MAX   __DEC64_MAX__
#define DEC128_MAX  __DEC128_MAX__

/* The difference between 1 and the least value greater than 1 that is
   representable in the given floating point type. */
#undef DEC32_EPSILON
#undef DEC64_EPSILON
#undef DEC128_EPSILON
#define DEC32_EPSILON        __DEC32_EPSILON__
#define DEC64_EPSILON        __DEC64_EPSILON__
#define DEC128_EPSILON        __DEC128_EPSILON__

/* Minimum normalized positive floating-point number. */
#undef DEC32_MIN
#undef DEC64_MIN
#undef DEC128_MIN
#define DEC32_MIN        __DEC32_MIN__
#define DEC64_MIN        __DEC64_MIN__
#define DEC128_MIN        __DEC128_MIN__

/* Minimum subnormal positive floating-point number. */
#undef DEC32_SUBNORMAL_MIN
#undef DEC64_SUBNORMAL_MIN
#undef DEC128_SUBNORMAL_MIN
#define DEC32_SUBNORMAL_MIN       __DEC32_SUBNORMAL_MIN__
#define DEC64_SUBNORMAL_MIN       __DEC64_SUBNORMAL_MIN__
#define DEC128_SUBNORMAL_MIN      __DEC128_SUBNORMAL_MIN__

/* The floating-point expression evaluation method.
         -1  indeterminate
         0  evaluate all operations and constants just to the range and
            precision of the type
         1  evaluate operations and constants of type _Decimal32 
            and _Decimal64 to the range and precision of the _Decimal64 
            type, evaluate _Decimal128 operations and constants to the 
            range and precision of the _Decimal128 type;
         2  evaluate all operations and constants to the range and
            precision of the _Decimal128 type.  */

#undef DEC_EVAL_METHOD
#define DEC_EVAL_METHOD        __DEC_EVAL_METHOD__

#endif /* __STDC_WANT_DEC_FP__ */

#endif /* _FLOAT_H___ */

#endif  /*_LIB_FLOAT_H*/
